Centrifugation allows to separate components of very variable size and mass contained in a liquid sample, from molecules to entire cells.
Such centrifugation techniques are conventionally implemented by means of laboratory centrifuges that comprise a chamber containing two rotating parts, i.e.:                a driving motor shaft, associated to motor means for the rotational operation thereof, and        a rotor, intended to be mounted on said motor shaft and intended to receive the containers in which are provided the liquid samples to be centrifuged.        
Conventionally, these two rotating parts are provided with complementary assembly means, for removably mounting the rotor on the free end of the driving motor shaft.
These assembly means comprise in particular means for locking in translation the two rotating parts associated to each other.
For example, in the document FR-2 951 964, these translation locking means comprise two male elements carried by the rotor, which are liable to occupy a position of cooperation with a female element arranged on the driving motor shaft.
These two male elements are each pivotally mounted about an axis of rotation extending parallel to a central longitudinal axis.
The rotor is mounted on the motor shaft by being simply fitted thereto, the male elements being retracted by being pushed by the rotor before being automatically locked in the active position within the above-mentioned female element.
To separate the rotor from the driving shaft, the operator must press simultaneously on two protruding lugs, diametrically opposed to each other, which are each carried by one of the pivoting male elements.
This action allows to operate the male elements to an inactive position, which corresponds to their separation from the female element, so as to make possible the translation of the rotor with respect to the driving motor shaft.
But, in practice, pressing on these lugs is not always easy and is not much ergonomic. It is indeed often necessary to exert a relatively high force to obtain the displacement of these lugs, and this with only the end of the fingers. Furthermore, the operation of these lugs requires a precise positioning of the fingers, which forces the operator to verify their orientation before manipulating them.
The operator must also displace entirely the two lugs; the differences of feeling when manipulating one and/or the other of these lugs might disturb the user, up to make him/her have doubts about the operation thereof between the locked and unlocked positions.
Such lugs are moreover liable to generate an aerodynamic noise; they are also relatively complex to clean, as the locking means are relatively open.